Drug patterned reinforcement material for circular anastomosis

ABSTRACT

A surgical stapling apparatus includes a staple cartridge assembly, an anvil assembly operatively associated with the staple cartridge assembly, and a surgical buttress releasably coupled to the staple cartridge assembly or the anvil assembly. The staple cartridge assembly includes a tissue facing surface having staple retaining slots defined therein, each staple retaining slot housing a staple therein, and a circular knife disposed radially inwardly of the tissue facing surface. The anvil assembly includes an anvil member including a tissue facing surface and an anvil shaft extending from the anvil member. The surgical buttress has a circular configuration defining a central aperture therethrough. The surgical buttress includes an inner concentric portion having a therapeutic coating disposed thereon and an outer concentric portion free of the therapeutic coating.

BACKGROUND Technical Field

The present disclosure relates to surgical buttresses that arereleasably attached to surgical stapling apparatus and moreparticularly, to surgical buttresses for local drug delivery.

Description of Related Art

Surgical stapling apparatus are employed by surgeons to sequentially orsimultaneously apply one or more rows of fasteners, e.g., staples ortwo-part fasteners, to body tissue for the purpose of joining segmentsof body tissue together and/or creating anastomoses.

Circular surgical stapling apparatus generally include a staplecartridge assembly including circular rows of staples, an anvil assemblyoperatively associated with the staple cartridge assembly, and acircular blade disposed internal to the circular rows of staples. Inuse, during an end-to-end circular anastomosis procedure, two ends ofhollow tissue sections, e.g., bowels, intestines, or other tubularorgans, are clamped between the anvil and staple cartridge assembliesand are joined by driving the circular rows of staples through theclamped hollow tissue sections. During firing of the staples, thecircular blade is advanced to cut portions of the tissue sectionsextending inside the staple lines, thereby establishing a passagethrough the two stapled tissue sections.

Surgical supports, e.g., meshes or buttress materials, may be used incombination with surgical stapling apparatus to bridge, repair, and/orreinforce tissue defects within a patient. The surgical supportreinforces the staple line as well as covers the juncture of the tissuesections to reduce incidents of, for example, tearing, leakage,bleeding, and/or strictures prior to healing.

Circular anastomosis may be utilized during tumor removal. For example,surgical resection of localized endoluminal tumors is part of thestandard of care for esophageal, gastric, and colorectal cancers. Oncean endoluminal tumor is excised, gastrointestinal conduits are oftenreconnected by forming a stapled circular anastomosis. Even withsurgery, however, each of these cancers is still associated with a highrate of post-surgical local recurrence. These cancers can be furthertreated with adjuvant systemic chemotherapy or radiotherapy, but each ofthese treatments can carry toxic side effects and/or be ineffective atreducing local recurrence.

Accordingly, it would be desirable to utilize a drug coated surgicalsupport at the site of a circular anastomosis to locally deliver drugssuch as chemotherapeutics, immunotherapies, or targeted therapies toreduce the risk of recurrence near the anastomosis.

SUMMARY

The present disclosure is directed to surgical buttresses including oneor more drugs patterned on select locations of the surgical buttress forlocalized drug delivery and treatment while protecting the underlyingtissue during anastomotic healing and allowing for normal tissueintegration into a majority of the surgical buttress.

A surgical stapling apparatus, in accordance with aspects of the presentdisclosure, includes a staple cartridge assembly, an anvil assemblyoperatively associated with the staple cartridge assembly, and asurgical buttress releasably coupled to the staple cartridge assembly orthe anvil assembly. The staple cartridge assembly includes a tissuefacing surface having staple retaining slots defined therein, eachstaple retaining slot housing a staple therein, and a circular knifedisposed radially inwardly of the tissue facing surface. The anvilassembly includes an anvil member including a tissue facing surface andan anvil shaft extending from the anvil member. The surgical buttresshas a circular configuration defining a central aperture therethrough.The surgical buttress includes an inner concentric portion having atherapeutic coating disposed thereon and an outer concentric portionfree of the therapeutic coating.

The inner concentric portion of the surgical buttress may include afirst concentric region extending radially inwardly of an inner stapleline of the surgical buttress, and a second concentric region extendingradially outwardly of the inner staple line to a middle staple line ofthe surgical buttress.

In embodiments, the therapeutic coating is disposed only within thefirst concentric region of the surgical buttress. In some embodiments,the first concentric region is defined between the inner staple line anda knife cut line of the surgical buttress and, in some otherembodiments, the first concentric region is defined between the innerstaple line and an inner edge of the surgical buttress. In certainembodiments, the inner edge of the surgical buttress is disposedradially inwardly of the circular knife of the staple cartridgeassembly. In embodiments, the therapeutic coating is disposed partiallywithin the second concentric region of the surgical buttress.

The therapeutic coating may include a chemotherapy drug or animmunotherapy drug. The therapeutic coating may be disposed on firstand/or second sides of the surgical buttress.

In some embodiments, the surgical buttress is disposed on the tissuefacing surface of the anvil assembly or the staple cartridge assemblyand, in some embodiments, the surgical buttress is disposed on the anvilshaft of the anvil assembly in spaced relation relative to the tissuefacing surfaces of the anvil and staple cartridge assemblies.

A staple cartridge assembly, in accordance with aspects of the presentdisclosure, includes a staple cartridge and a surgical buttress. Thestaple cartridge includes a tissue facing surface having stapleretaining slots defined therein, each staple retaining slot housing astaple therein, and a circular knife disposed radially inwardly of thetissue facing surface. The surgical buttress is releasably disposed onthe tissue facing surface of the staple cartridge. The surgical buttresshas a circular configuration defining a central aperture therethrough.The surgical buttress includes an inner concentric portion having atherapeutic coating disposed thereon and an outer concentric portionfree of the therapeutic coating.

The inner concentric portion of the surgical buttress may include afirst concentric region extending radially inwardly of an inner stapleline of the surgical buttress, and a second concentric region extendingradially outwardly of the inner staple line to a middle staple line ofthe surgical buttress.

In embodiments, the therapeutic coating is disposed only within thefirst concentric region of the surgical buttress. In some embodiments,the first concentric region is defined between the inner staple line anda knife cut line of the surgical buttress and, in some otherembodiments, the first concentric region is defined between the innerstaple line and an inner edge of the surgical buttress. In certainembodiments, the inner edge of the surgical buttress is disposedradially inwardly of the circular knife of the staple cartridge. Inembodiments, the therapeutic coating is disposed partially within thesecond concentric region of the surgical buttress. In yet otherembodiments, the drug can be applied in any number of arrangements orpatterns on the buttress to produce the desired effect of drug deliveryand tissue integration into portions of the drug loaded buttress.

The therapeutic coating may include a chemotherapy drug or animmunotherapy drug. The therapeutic coating may be disposed on firstand/or second sides of the surgical buttress.

Other aspects, features, and advantages will be apparent from thedescription, drawings, and the claim.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the present disclosure are described herein belowwith reference to the drawings, which are incorporated in and constitutea part of this specification, wherein:

FIG. 1A is a side, perspective view of a surgical stapling apparatus inaccordance with an embodiment of the present disclosure;

FIG. 1B is a bottom, perspective view of an anvil assembly of thesurgical stapling apparatus of FIG. 1A;

FIG. 2 is a partial cross-sectional view of the surgical staplingapparatus shown in FIG. 1A, including surgical buttresses releasablyattached thereto in accordance with an embodiment of the presentdisclosure;

FIG. 3A is a top, plan view of a surgical buttress of FIG. 2, in aninitial configuration prior to actuation of the surgical staplingapparatus;

FIG. 3B is a top, plan view of the surgical buttress of FIG. 3A, in afinal configuration after actuation of the surgical stapling apparatus;

FIG. 4A is a top, plan view of a surgical buttress in accordance withanother embodiment of the present disclosure;

FIG. 4B is a top, plan view of a surgical buttress in accordance withyet another embodiment of the present disclosure;

FIG. 5 is a top, plan view of a surgical buttress in accordance with anembodiment of the present disclosure;

FIG. 6 is a partial cross-sectional view of the surgical staplingapparatus shown in FIG. 1A including a surgical buttress releasablyattached thereto in accordance with another embodiment of the presentdisclosure; and

FIG. 7 is a top, plan view of the surgical buttress of FIG. 6, in aninitial configuration prior to actuation of the surgical staplingapparatus.

DETAILED DESCRIPTION

Various exemplary embodiments of the present disclosure are discussedherein below in terms of surgical buttresses for use with a surgicalstapling apparatus. The surgical buttresses described herein may be usedin sealing a wound by approximating the edges of tissue between a staplecartridge assembly and an anvil assembly of the surgical staplingapparatus which includes at least one surgical buttress. The surgicalbuttress is releasably attached to the surgical stapling apparatus suchthat staples fired from the surgical stapling apparatus attach thesurgical buttress to tissue.

While the surgical buttresses are discussed in conjunction with asurgical stapling apparatus, it is envisioned that other surgicalapparatus and/or fixation devices, such as tacks, sutures, clips,adhesives, and the like, may be utilized to affix surgical buttresses ofthe present disclosure to tissue. It should also be appreciated thatwhile the principles of the present disclosure are described withrespect to surgical buttresses, the buttressing materials of the presentdisclosure are suitable for use in a variety of medical devices tomechanically support and/or reinforce tissue such as, for example,hernia meshes, patches, stents, pledgets, and/or scaffolds.

Embodiments of the presently disclosed surgical buttresses will now bedescribed in detail with reference to the drawing figures wherein likereference numerals identify similar or identical elements. Throughoutthis description, the term “proximal” refers to a portion of astructure, or component thereof, that is closer to a user, and the term“distal” refers to a portion of the structure, or component thereof,that is farther from the user.

Referring now to FIG. 1A, a surgical stapling apparatus or circularstapler 10 for use in stapling tissue and applying a surgical buttressto tissue is shown. The surgical stapling apparatus 10 includes a handleassembly 20, an elongated tubular body 30 extending distally from thehandle assembly 20, an anvil assembly 40 releasably coupled to a distalend portion 32 of the elongated tubular body 30, and a staple cartridgeassembly 50 disposed at the distal end portion 32 of the elongatedtubular body 30.

The handle assembly 20 includes at least one movable handle member 22for actuating the firing of staples 54 (FIG. 2) from the staplecartridge assembly 50 and the cutting of tissue secured between theanvil and staple cartridge assemblies 40, 50. The handle assembly 20further includes an advancing member 24 for moving the anvil assembly 40between an open or spaced apart position and a closed or approximatedposition relative to the staple cartridge assembly 50.

The elongated tubular body 30 may be flexible or rigid, and/or straightor curved along a portion or the entirety thereof. It should beunderstood that the elongated tubular body 30 may be otherwiseconfigured (e.g., shaped and/or dimensioned) depending on, for example,the surgical application or procedure of use as is within the purview ofthose skilled in the art. The staple cartridge assembly 50 may befixedly connected to the distal end portion 32 of the elongated tubularbody 30 or may be configured to concentrically fit within, or beotherwise connected to, the distal end portion 32 of the elongatedtubular body 30 such that the staple cartridge assembly 50 is removableand replaceable.

As shown in FIGS. 1A and 1B, the anvil assembly 40 includes an anvilmember 42 having a tissue facing surface 44 defined by an outerperimeter 44 a and an inner perimeter 44 b. Staple forming recesses 43(e.g., a circular array or circular rows of staple forming recesses) aredefined in the tissue facing surface 44 of the anvil member 42. Thestaple forming recesses 43 mirror staple retaining slots 51 of thestaple cartridge assembly 50 (e.g., corresponding in position, size,and/or shape). The anvil assembly 40 further includes an anvil shaft 46extending distally from the anvil member 42. The anvil shaft 46 isreleasably connectable to the elongated tubular body 30 of the surgicalstapling apparatus 10.

The anvil shaft 46 of the anvil assembly 40 may be connected to a rod 34extending through the elongated tubular body 30. The rod 34 can beoperably coupled to the advancing member 24 of the handle assembly 20such that, when the anvil shaft 46 is attached to the rod 34, rotationof the advancing member 24 results in longitudinal movement of the rod34 which, in turn, results in longitudinal movement of the anvilassembly 40 relative to the elongated tubular body 30. For example, whenthe advancing member 24 is rotated in a first direction, the anvilassembly 40 is moved away from the elongated tubular body 30, allowingtissue to be placed between the anvil and staple cartridge assemblies40, 50 and, when the advancing member 24 is rotated in a seconddirection, the anvil assembly 40 is moved toward the elongated tubularbody 30, allowing the tissue to be clamped between the anvil and staplecartridge assemblies 40, 50. It should be understood that othermechanisms for moving the anvil assembly 40 with respect to theelongated tubular body 30 are contemplated and within the purview ofthose skilled in the art.

As shown in FIGS. 1A and 2, the staple cartridge assembly 50 includes atissue facing surface 52 defined by an outer perimeter 52 a and an innerperimeter 52 b. Staple retaining or receiving slots 51 (e.g., a circulararray or circular rows of staple retaining slots) are defined in thetissue facing surface 52 of the staple cartridge assembly 50, with astaple 54 disposed in each of the staple retaining slots 51. While thestaple cartridge assembly 50 is shown including three circular rows ofstaple retaining slots 51, it should be understood that the staplecartridge assembly 50 may include one or more rows, or partial rows, ofstaple retaining slots 51 in a variety of arrangements in the tissuefacing surface 52 of the staple cartridge assembly 50 (e.g., the rowsand/or partial rows may be circular, oval, polygonal, etc.). It shouldfurther be understood that the shape of the staple retaining slots 51may vary (e.g., the staple retaining slots may have a curved or angledshape) to accommodate the positioning of the staples 54 relative to eachother, and/or the size of the staple retaining slots 51 may vary (e.g.,one or more rows of staple retaining slots may be different in size fromother row(s) of staple retaining slots) to accommodate different shapedand/or sized staples 54.

A staple pusher 56 is disposed in the staple cartridge assembly 50 andhas a plurality of fingers or pushers 57 that are aligned with thestaple retaining slots 51. The staple pusher 56 is movable in a distaldirection to drive the staples 54 out of the staple cartridge assembly50. A knife 58, substantially in the form of an open cup having acylindrical shape with a rim thereof defining a knife blade 59, isdisposed radially inwardly of the pushers 57. The knife 58 is mounted toa surface of the staple pusher 56 so that, in use, as the staple pusher56 is advanced distally, the knife 58 is also advanced distally (e.g.,axially outward) such that after the staples 54 are driven throughtissue captured between the anvil and staple cartridge assemblies 40,50, the portions of the tissue disposed radially inwardly of the staples54 are cut by the knife blade 59.

The movable handle members 22 of the handle assembly 20 can be operablycoupled to the staple pusher 56 by, for example, a tubular member orpair of bands (not shown) that are attached to the staple pusher 56 by,for example, linkages or the like. In this way, when the movable handlemembers 22 are actuated, the tubular member or bands are advanced,advancing the staple pusher 56, as described above. It should beunderstood that other mechanisms for firing the surgical staplingapparatus 10 are contemplated and within the purview of those skilled inthe art.

For a detailed description of the structure and function of exemplarysurgical stapling apparatus, reference may be made to U.S. Pat. Nos.4,473,077; 4,576,167; 5,005,749; 5,119,983; 5,588,579; 5,915,616; and6,053,390, the entire content of each of which is incorporated herein byreference. It should be understood that a variety of circular surgicalstapling apparatus may be utilized with the surgical buttresses of thepresent disclosure. For example, circular staplers, such as, forexample, EEA™ and CEEA™ staplers, available through Medtronic (NorthHaven, Conn.) may be utilized with the surgical buttresses of thepresent disclosure.

As shown in FIG. 2, surgical buttresses 60 are releasably attached tothe tissue facing surfaces 44, 52 of the anvil and staple cartridgeassemblies 40, 50, respectively. The surgical buttresses 60 may bereleasably secured to the tissue facing surfaces 44, 52 of the anviland/or staple cartridge assemblies 40, 50 via any suitable attachmentfeature within the purview of those skilled in the art, such as,chemical attachment features (e.g., adhesives), mechanical attachmentfeatures (e.g., mounting structures, such as tabs, pins, or straps),and/or attachment methods (e.g., welding). For a detailed description ofexemplary attachment features suitable for use with a surgical buttressof the present disclosure, reference may be made to U.S. Pat. Nos.8,584,920; 8,967,448; and 9,237,892, the entire content of each of whichis incorporated herein by reference. In embodiments, an adhesive (notexplicitly shown) is disposed between the surgical buttresses 60 and therespective tissue facing surface 44, 52 of the anvil and staplecartridge assemblies 40, 50.

The surgical stapling apparatus 10 and detachable anvil assembly 40 areused in an anastomosis procedure to effect joining of tissue sections 1,2 (e.g., intestinal or other tubular organ sections). The anastomosisprocedure is typically performed using minimally invasive surgicaltechniques including laparoscopic means and instrumentation. At thepoint in the procedure shown in FIG. 2, such as after removal of adiseased tissue section, the anvil assembly 40 has been applied to theoperative site (e.g., through a surgical incision or a body orifice) andpositioned within tissue section 1, the elongated tubular body 30 of thesurgical stapling apparatus 10 has been inserted (e.g., through asurgical incision or a body orifice) within tissue section 2, and theanvil shaft 46 of the anvil assembly 40 has been connected to theelongated tubular body 30. The tissue sections 1, 2 are also showntemporarily secured about their respective components by conventionalmeans such as purse string sutures “P”.

Thereafter, the anvil assembly 40 is approximated towards the elongatedtubular body 30 (e.g., via advancing member 24 (FIG. 1) of the handleassembly 20) to approximate the tissue sections 1, 2. The surgicalstapling apparatus 10 is then actuated (e.g., via movable handle members22 (FIG. 1) of the handle assembly 20), firing the staples 54 from thestaple cartridge assembly 50 and towards the anvil member 42 of theanvil assembly 40 to effect stapling of the tissue sections 1, 2 to oneanother, as well as the surgical buttresses 60 to the tissue sections 1,2. The knife blade 59 cuts the now stapled tissue sections 1, 2, as wellas any portion of the surgical buttresses 60 extending radially inwardlyof the knife 58, to complete the anastomosis. Upon movement of the anvilassembly 40 away from staple cartridge assembly 50 (e.g., via advancingmember 24), the surgical buttresses 60, which are now stapled to thetissue sections 1, 2, are pulled away from the anvil and staplecartridge assemblies 40, 50.

The surgical buttresses of the present disclosure are fabricated frombiocompatible materials which are bioabsorbable or non-absorbable,natural or synthetic materials. It should be understood that anycombination of natural, synthetic, bioabsorbable, and/ornon-bioabsorbable materials may be used to form a surgical buttress. Thesurgical buttresses of the present disclosure may be biodegradable(e.g., formed from bioabsorbable and bioresorable materials) such thatthe surgical buttresses decompose or are broken down (physically orchemically) under physiological conditions in the body, and thedegradation products are excretable or absorbable by the body.

The surgical buttresses may be porous, non-porous, or combinationsthereof. Suitable porous structures include, for example, fibrousstructures (e.g., knitted structures, woven structures, and non-wovenstructures) and/or foams (e.g., open or closed cell foams). Suitablenon-porous structures include, for example, films. The surgicalbuttresses may be a single porous or non-porous layer, or include aplurality of layers including any combination of porous and/ornon-porous layers.

Porous layer(s) in a surgical buttress may enhance the ability of thesurgical buttress to absorb fluid, reduce bleeding, and seal a wound.Also, the porous layer(s) may allow for tissue ingrowth to fix thesurgical buttress in place. Non-porous layer(s) in a surgical buttressmay enhance the ability of the surgical buttress to resist tears andperforations during the manufacturing, shipping, handling, and staplingprocesses. Also, non-porous layer(s) may retard or prevent tissueingrowth from surrounding tissues thereby acting as an adhesion barrierand preventing the formation of unwanted scar tissue. The porosity ofthe layer(s) of the surgical buttress may allow for and/or determine therate of infiltration of biological fluids and/or cellular componentsinto the surgical buttress which, in turn, may accelerate or deceleratethe release kinetics of therapeutic agent(s) from the surgical buttressand thus, increase or decrease the release rate of the therapeuticagent(s) from the surgical buttress into the surrounding tissue andfluids.

The surgical buttresses of the present disclosure include a therapeuticcoating disposed thereon. The therapeutic coating provides treatment inthe form of chemotherapy, immunotherapy, targeted therapy, orcombinations thereof by local delivery of one or more therapeutic agentsor anti-cancer drugs at the site of tumor resection. The therapeuticcoating may include one or more therapeutic agents therein having one ormore release profiles. The surgical buttresses of the present disclosuremay release therapeutic agent(s) therefrom over a period of time fromabout 12 hours to about 6 weeks, in embodiments, from about 24 hours toabout 4 weeks and, in some embodiments, from about 48 hours to about 2weeks.

The therapeutic agent(s) of the therapeutic coating may include, but arenot limited to, drugs (e.g., small molecule drugs), amino acids,peptides, polypeptides, proteins, polysaccharides, muteins,immunoglobulins, antibodies, cytokines (e.g., lymphokines, monokines,chemokines), blood clotting factors, hemopoietic factors, interleukins(1 through 18), interferons (β-IFN, α-IFN and γ-IFN), erythropoietin,nucleases, tumor necrosis factor, colony stimulating factors (e.g.,GCSF, GM-CSF, MCSF), insulin, anti-tumor agents, tumor suppressors,blood proteins, fibrin, thrombin, fibrinogen, synthetic thrombin,synthetic fibrin, synthetic fibrinogen, gonadotropins (e.g., FSH, LH,CG, etc.), hormones and hormone analogs (e.g., growth hormone,luteinizing hormone releasing factor), vaccines (e.g., tumoral,bacterial, and viral antigens), somatostatin, antigens, bloodcoagulation factors, growth factors (e.g., nerve growth factor,insulin-like growth factor), bone morphogenic proteins, TGF-B, proteininhibitors, protein antagonists, protein agonists, nucleic acids, suchas antisense molecules, DNA, RNA, RNAi, oligonucleotides,polynucleotides, cells, viruses, and ribozymes.

In embodiments, the therapeutic coating includes an anti-tumor agentand/or tumor suppressor, referred to, in embodiments, as a“chemotherapeutic agent” and/or an “antineoplastic agent.” Suitablechemotherapeutic agents include, for example, paclitaxel and derivativesthereof, docetaxel and derivatives thereof, abraxane, tamoxifen,cyclophosphamide, actinomycin, bleomycin, dactinomycin, daunorubicin,doxorubicin, doxorubicin hydrochloride, epirubicin, mitomycin,methotrexate, fluorouracil, gemcitabine, gemcitabine hydrochloride,carboplatin, carmustine (BCNU), methyl-CCNU, cisplatin, etoposide,camptothecin and derivatives thereof, phenesterine, vinblastine,vincristine, goserelin, leuprolide, interferon alfa, retinoic acid(ATRA), nitrogen mustard alkylating agents, piposulfan, vinorelbine,irinotecan, irinotecan hydrochloride, vinblastine, pemetrexed, sorafenibtosylate, everolimus, erlotinib hydrochloride, sunitinib malate,capecitabine oxaliplatin, leucovorin calcium, bevacizumab, cetuximab,ramucirumab, trastuzumab, combinations thereof, and the like.

In some embodiments, the therapeutic coating includes paclitaxel and/orpaclitaxel derivatives as the therapeutic agent. Paclitaxel may havevarious forms, referred to herein as “polymorphs,” including amorphouspaclitaxel, crystalline paclitaxel, sometimes referred to as crystallinepaclitaxel dihydrate, and/or anhydrous paclitaxel, or mixtures thereof.The polymorph form of paclitaxel in the therapeutic coating may beadjusted and selected to provide a tailored release of the therapeuticagent from the surgical buttress of the present disclosure as thecrystallinity of the paclitaxel impacts its solubility in aqueoussystems. Although the drug in any form is hydrophobic, as amorphouspaclitaxel it is more soluble in aqueous environments, and crystallinepaclitaxel is less soluble in aqueous environments, more than onepolymorphic form of paclitaxel may be used, in embodiments, to providesurgical buttresses that have multiple release profiles of paclitaxel.

For example, surgical buttresses of the present disclosure having bothamorphous paclitaxel and crystalline paclitaxel dihydrate thereon mayrelease a bolus of therapeutic agent upon implantation (in the form ofthe amorphous paclitaxel), while also slowly releasing the therapeuticagent (in the form of the crystalline paclitaxel dihydrate). Inembodiments, surgical buttresses of the present disclosure may releaseamorphous paclitaxel over a period of time from about 24 hours to about168 hours, in some embodiments, from about 48 hours to about 96 hours,and release crystalline paclitaxel dihydrate over a period of time fromabout 1 week to about 6 weeks, in some embodiments, from about 2 weeksto about 4 weeks.

The therapeutic coating of the surgical buttresses of the presentdisclosure may include a carrier component formed from, for example,polymeric materials such as, but not limited to, degradable materialssuch as those prepared from monomers such as glycolide, lactide,trimethylene carbonate, p-dioxanone, epsilon-caprolactone, andcombinations thereof.

The therapeutic coating, regardless of whether the therapeutic agent isapplied with or without a carrier component, may include excipient(s) toenhance both the ability of the therapeutic agent to adhere to thesurgical buttress as well as to modify the elution of the therapeuticagent therefrom. Suitable excipients include, but are not limited to,surfactants (e.g., cyclodextrins or sorbitan fatty acid esters), lowmolecule weight poly (ethylene glycol)s, salts (e.g., sodium chlorideand/or other materials such as urea, oleic acid, citric acid, andascorbic acid), stabilizers (e.g., butylated hydroxytoluene), polyhydricalcohols (e.g., D-sorbitol or mannitol), combinations thereof, and thelike. In some embodiments, excipients which are hydrotropes may beincluded in the therapeutic coating of the present disclosure. Thesematerials attract water into the therapeutic coating, which may enhanceits degradation and resulting release of the therapeutic agenttherefrom.

The therapeutic coating or components thereof (e.g., therapeuticagent(s), carrier component(s), and/or excipient(s)) may be in asolution for application to a surgical buttress of the presentdisclosure. Suitable solvents for forming such a solution include anypharmaceutically acceptable solvent including, but not limited to,saline, water, alcohol, acetone, dimethyl sulfoxide, ethyl acetate,N-methylpyrrolidone, combinations thereof, and the like. Methods forforming such solutions are within the purview of those skilled in theart and include, but are not limited to, mixing, blending, sonication,heating, combinations thereof, and the like. Methods for driving off thesolvent after application to the surgical buttress to form thetherapeutic coating and leave the therapeutic agent and any carriercomponent and/or excipient behind are within the purview of thoseskilled in the art and include, for example, solvent evaporation byheat, gas flow, time, reduced pressure, combinations thereof, and thelike. By selecting different solvent systems, different dissolutionrates of the therapeutic agent(s) may be achieved due to differenttherapeutic agent morphologies and degrees of crystallinity that occurbased upon the solvent used in forming the solution including thetherapeutic agent(s).

The therapeutic coating is disposed over specific areas of the surgicalbuttress such that the therapeutic agent(s) is deposited on the surgicalbuttress with high precision, and other areas of the surgical buttressare left uncoated by design to improve the performance of the surgicalbuttress, for instance, for better tissue healing around staple lines.The therapeutic coating or components thereof may be applied to thesurgical buttress of the present disclosure by needle depositionprocesses, inkjet printing techniques, deposition methods includingpiezoelectric elements, combinations thereof, and the like.

The application process may include one or more passes of thetherapeutic coating or components thereof onto the surgical buttress toensure the surgical buttress has the desired amount of therapeutic agentfor administering a dose of the therapeutic agent. In embodiments,multiple layers of the therapeutic coating is deposited on the surgicalbuttress resulting in an overall therapeutic coating that is uniform androbust, and adheres well to the buttress material. This is in contrastto other processes, such as dip coating and other similar coatingmethods, which lack both the robustness and adherence of thecoatings/layers produced in accordance with the present disclosure. Insome embodiments, different therapeutic agents are applied in differentlayers of the therapeutic coating. Different therapeutic benefits canthus be combined on one surgical buttress by using the multiple layers.In certain embodiments, different therapeutic agents can be deposited ondifferent areas on the surface of the surgical buttress, e.g., onetherapeutic agent can be applied in one region or area of the surgicalbuttress, and a different therapeutic agent can be applied to adifferent region or area of the surgical buttress.

With reference now to FIG. 3A, the surgical buttress 60 has a generallycircular or annular configuration defining a central aperture 61therethrough. The central aperture 61 is sized and dimensioned to allowfree passage of the anvil shaft 46 of the anvil assembly 40therethrough. In embodiments, the central aperture 61 has a diameterthat is larger than the diameter of the anvil shaft 46 of the anvilassembly 40. In some embodiments, the diameter of the central aperture61 may be about the same as or smaller than the diameter of the anvilshaft 46.

The surgical buttress 60 includes a body 62 having an outer edge 62 aand an inner edge 62 b defining the central aperture 61 of the surgicalbuttress 60. The body 62 is sized and dimensioned to extend over (e.g.,completely cover) the tissue facing surface 44, 52 of the anvil orstaple cartridge assembly 40, 50, with the outer edge 62 a of the body62 aligned (e.g., radially) and coincident with the outer perimeter 44a, 52 a of the anvil or staple cartridge assembly 40, 50 and the inneredge 62 a disposed radially inwardly of the knife 58 of the staplecartridge assembly 50. In some embodiments, the outer edge 62 a of thebody 62 of the surgical buttress 60 extends radially beyond the outerperimeter 44 a, 52 a of the anvil or staple cartridge assembly 40, 50.

The body 62 of the surgical buttress 60 includes a plurality ofconcentric regions 64 defined therein. A first or inner concentricregion 64 a is defined between a knife cut line 66 a and a first orinner staple line 66 b of the surgical buttress 60, a second concentricregion 64 b is defined between the first staple line 66 b and a secondor middle staple line 66 c of the surgical buttress 60, a thirdconcentric region 64 c is defined between the second staple line 66 cand a third or outer staple line 66 d of the surgical buttress 60, and afourth concentric region 64 d is defined between the third staple line66 d and the outer edge 62 a of the surgical buttress 60. The knife cutline 66 a of the surgical buttress 60 is aligned with the knife 58 ofthe staple cartridge assembly 50, and the first, second, and thirdstaple lines 66 b, 66 c, 66 d of the surgical buttress 60 are alignedwith the staple forming recesses 43 or the staple forming slots 51 ofthe anvil or staple cartridge assembly 40, 50.

A therapeutic coating 68 is disposed on the first concentric region 64 aof the surgical buttress 60 such that the therapeutic coating 68 extendsbetween the knife cut line 66 a and the first staple line 66 b of thesurgical buttress 60. The therapeutic coating 68 is applied so that anadequate amount of therapeutic agent(s) is deposited on and robustlyattached to the first concentric region 64 a of the surgical buttress60, while the remainder of the surgical buttress 60 (e.g., the second,third, and fourth concentric regions 64 b, 64 c, 64 d) remain free ofthe therapeutic coating 68 and thus, any therapeutic agent(s). Thetherapeutic coating 68 may be disposed on one or both sides of thesurgical buttress 60 (e.g., one side contacting the tissue facingsurface 44, 52 of the anvil or staple cartridge assembly 40, 50 and anopposed side facing away from the tissue facing surface 44, 52).

While the therapeutic coating 68 is shown as a continuous layer coveringthe entirety of the first concentric region 64 a of the surgicalbuttress 60, it should to be appreciated that the configuration of thetherapeutic coating 68 may vary. For example, the therapeutic coating 68may be a discontinuous or patterned layer disposed on the surgicalbuttress 60. In some embodiments, the therapeutic coating 68 may bedisposed within a portion of the first concentric region 64 a of thesurgical buttress 60 in spaced relation from, and radially inwardly of,the first staple line 66 b.

Upon actuation of the surgical stapling device 10, the portion of thesurgical buttress 60 disposed radially inwardly of the knife cut line 66a of the surgical buttress 60 is cut away from the surgical buttress 60by the knife 58 of the staple cartridge assembly 50. As shown in FIG.3B, in a final configuration of the surgical buttress 60, the centralaperture 61′ is enlarged and defined by an inner edge 62 b′ coincidentwith the knife cut line 66 a (FIG. 3A), and staples 54 extend throughthe surgical buttress 60 in circular staple rows or lines “S1”, “S2”,and “S3” coincident with the first, second, and third staple lines 66 b,66 c, 66 d (FIG. 3A), respectively, of the surgical buttress 60. Thetherapeutic coating 68, disposed on the first concentric region 64 a ofthe surgical buttress 60, allows the therapeutic agent(s) of thetherapeutic coating 68 to diffuse into the endoluminal space and intolocal tissue, while not impacting healing over a majority of thecircular staple lines “S1”, “S2”, and “S3”. For example, in the case oftumor resection, the therapeutic coating 68 may eradicate any remainingtumor cells, stimulate a host response to destroy tumor cells, and/orblock pathways required for tumor growth that may lead to a recurrentcancer. The precise location of the therapeutic coating 68 on thesurgical buttress 60 isolates the therapeutic agent to areas where it isintended to be used (e.g., eliminates toxicity associated with systemicchemotherapy), delivers continuous and prolonged local therapy, and/orprovides costs savings in terms of the amount of therapeutic agent used(e.g., reduces the drug payload compared to conventional systemicchemotherapy).

While the therapeutic coating 68 is shown disposed only within the firstconcentric region 64 a of the surgical buttress 60, other configurationsare envisioned. The therapeutic coating 68 may be disposed on any partof an inner concentric portion 63 a of the body 62 of the surgicalbuttress 60, which includes portions of the surgical buttress 60disposed radially inwardly of the second staple line 66 c. An outerconcentric portion 63 b of the body 62, which includes portions of thesurgical buttress 60 disposed radially outwardly of the second stapleline 66 c, is to remain free of the therapeutic coating 68.

For example, as shown in FIG. 4A, a surgical buttress 60′ in accordancewith another embodiment of the present disclosure is substantially thesame as surgical buttress 60 except that the therapeutic coating 68′extends radially inwardly of the knife cut line 66 a towards the inneredge 62 b of the surgical buttress 60′. Accordingly, in someembodiments, the first concentric region 64 a′ of the surgical buttress60′ is defined between the inner edge 62 b of the surgical buttress andthe first staple line 66 b, and the therapeutic coating 68′ is disposedover the entirety or portion(s) thereof.

As another example, as shown in FIG. 4B, a surgical buttress 60″ inaccordance with another embodiment of the present disclosure issubstantially the same as surgical buttress 60 except that thetherapeutic coating 68″ extends radially outwardly of the first stapleline 66 b towards the second staple line 66 c. Accordingly, in someembodiments, the therapeutic coating 68″ is disposed on the firstconcentric region 64 a of the surgical buttress 60″ and a portion of thesecond concentric region 64 b of the surgical buttress 60″ in spacedrelation from, and radially inwardly of, the second staple line 66 c. Incertain embodiments, the therapeutic coating 68″ is disposed on aportion or the entirety of the first and/or second concentric regions 64a, 64 b of the surgical buttress 60″.

With reference now to FIG. 5, a surgical buttress 70 in accordance withanother embodiment of the present disclosure is shown. The surgicalbuttress 70 includes a body portion 72 including an outer edge 72 a andan inner edge 72 b, the inner edge 72 b defining a central aperture 71of the surgical buttress 70. The surgical buttress 70 is sized anddimensioned such that the body portion 72 extend over the tissue facingsurface 44, 52 of the anvil or staple cartridge assembly 40, 50 to whichthe surgical buttress 70 is releasably secured. The outer edge 72 a ofthe body 72 is radially aligned or coincident with the outer perimeter44 a, 52 a of the anvil or staple cartridge assembly 40, 50 and theinner edge 72 a is radially aligned or coincident with the innerperimeter 44 b, 52 b of the anvil or staple cartridge assembly 40, 50such that the inner edge 72 b is disposed radially inwardly of thestaple forming recesses 43 or the staple retaining slots 51 of the anvilor staple cartridge assembly 40, 50, and radially outwardly of the knife58.

A therapeutic coating 78 is disposed on a first concentric region 74 aof the surgical buttress 70 that is defined between the inner edge 72 bof the surgical buttress 70 and a first or inner staple line 76 a of thesurgical buttress 70. It should be understood that the therapeuticcoating 78 may extend partially or completely through the firstconcentric region 74 a and, in some embodiments, may extend completelyor partially into a second concentric region 74 b of the surgicalbuttress 70 that is defined between the first staple line 76 a and asecond or middle staple line 76 b of the surgical buttress 70.

Upon actuation of the surgical stapling apparatus 10, the surgicalbuttress 70 remains intact and is not cut by the knife 58 which, forexample, may reduce the firing force required to cut through the stapledtissue and the surgical buttress 70. Accordingly, the size of thecentral aperture 71 does not change between initial and finalconfigurations of the surgical buttress 70. The body 72 of the surgicalbuttress 70 is attached to tissue via staples 54 (FIG. 3B) as describedabove with respect to the surgical buttress 60.

It should be understood that while the surgical stapling apparatus isshown including surgical buttresses disposed on both the anvil and thestaple cartridge assemblies, the surgical stapling apparatus may includeonly one surgical buttress disposed on either the anvil assembly or thestaple cartridge assembly. It should be further understood that any ofthe surgical buttresses of the present disclosure may be disposed on theanvil and/or staple cartridge assemblies depending on, for example, thesurgical application and/or desired placement of the buttress materialrelative to tissue as should be understood by those skilled in the art.

The surgical buttress(es) of the present disclosure may be pre-loaded(e.g., by the manufacturer) onto the anvil assembly and/or the staplecartridge assembly. Additional or replacement surgical buttresses may besecured to the respective anvil and/or staple cartridge assemblies asneeded or desired.

It is envisioned that the surgical buttress may be, additionally oralternatively, positioned on the anvil shaft of the anvil assemblyfollowing the connection of the anvil assembly to the respective tissuesection such that the surgical buttress is stapled between the tissuesections following actuation of the surgical stapling apparatus.

With reference now to FIGS. 6 and 7, a surgical buttress 80 isreleasably attached to the anvil assembly 40 by positioning the anvilshaft 46 through a central aperture 81 of the surgical buttress 80 suchthat the surgical buttress 80 engages the anvil shaft 46 (e.g.,frictional engagement) and a body 82 of the surgical buttress 80 isdisposed in axially spaced relation relative to the tissue facingsurfaces 44, 52 of the anvil and/or staple cartridge assemblies 40, 50.At the point of a surgical procedure shown in FIG. 6, after a diseasedtissue section has been removed and the anvil and staple cartridgeassemblies 40, 50 have been positioned within the respective tissuesections 1, 2 and temporarily secured thereabout with purse stringsutures “P”, the surgical buttress 80 is placed on the anvil shaft 46 ofthe anvil assembly 40 and then the anvil shaft 46 is connected to theelongated tubular body 30. Thereafter, the anvil assembly 40 isapproximated towards the elongated tubular body 30 to capture thesurgical buttress 80 between the tissue sections 1, 2, and the surgicalstapling apparatus 10 is fired, as discussed above, thereby stapling thetissue sections 1, 2 and surgical buttress 80 to each another andcutting the portions of the tissue and the surgical buttress 80 disposedradially inward of the knife 58 to complete the anastomosis.

The surgical buttress 80 includes a body portion 82 including an outeredge 82 a and an inner edge 82 b, the inner edge 82 b defining a centralaperture 81 of the surgical buttress 80. The diameter of the centralaperture 81 is about the same as or smaller than the diameter of theanvil shaft 46. The outer edge 82 a of the body 82 is radially alignedor coincident with the outer perimeter 44 a, 52 a of the anvil or staplecartridge assembly 40, 50, and the inner edge 72 a is engagable with theanvil shaft 46, as discussed above, such that the inner edge 72 b isdisposed radially inwardly of the knife 58.

A therapeutic coating 88 is disposed on a first concentric region 84 aof the surgical buttress 80 that is defined between a knife cut line 86a of the surgical buttress 80 and a first or inner staple line 86 b ofthe surgical buttress 80. It should be understood that the therapeuticcoating 88 may extend partially or completely through the firstconcentric region 84 a and, in some embodiments, may extend completelyor partially into a second concentric region 84 b of the surgicalbuttress 80 that is defined between the first staple line 86 b and asecond or middle staple line 86 c of the surgical buttress 70. Moreover,while the therapeutic coating 88 is shown disposed on first and secondsides 80 a, 80 b of the surgical buttress 80, it should be understoodthat the therapeutic coating 88 may disposed on only one of the first orsecond sides 80 a, 80 b.

Although the surgical stapling apparatus discussed above has a manuallyoperated, manually driven handle, any of the embodiments disclosedherein can include a surgical stapling apparatus having a hand-heldpowered handle having a motor, or a stapling unit that is attachable toa motorized drive, or a stapling unit arranged for use in a roboticsurgical system. The surgical buttresses described herein may also beconfigured for use with other surgical apparatus, such aselectromechanical surgical devices as described, for example, in U.S.Patent Appl. Pub. Nos. 2015/0157320 and 2015/0157321, the entirecontents of each of which are incorporated herein by reference.

Persons skilled in the art will understand that the devices and methodsspecifically described herein and illustrated in the accompanyingfigures are non-limiting exemplary embodiments, and that thedescription, disclosure, and figures should be construed merelyexemplary of particular embodiments. It is to be understood, therefore,that the present disclosure is not limited to the precise embodimentsdescribed, and that various other changes and modifications may beaffected by one skilled in the art without departing from the scope orspirit of the disclosure. Additionally, it is envisioned that theelements and features illustrated or described in connection with oneexemplary embodiment may be combined with the elements and features ofanother exemplary embodiment without departing from the scope of thepresent disclosure, and that such modifications and variations are alsointended to be included within the scope of the present disclosure.Accordingly, the subject matter of the present disclosure is not to belimited by what has been particularly shown and described.

What is claimed is:
 1. A surgical stapling apparatus comprising: astaple cartridge assembly including a tissue facing surface havingstaple retaining slots defined therein, each staple retaining slothousing a staple therein, and a circular knife disposed radiallyinwardly of the tissue facing surface; an anvil assembly operativelyassociated with the staple cartridge assembly, the anvil assemblyincluding an anvil member including a tissue facing surface and an anvilshaft extending from the anvil member; and a surgical buttressreleasably coupled to the staple cartridge assembly or the anvilassembly, the surgical buttress having a circular configuration defininga central aperture therethrough, the surgical buttress including aninner concentric portion having a therapeutic coating disposed thereonand an outer concentric portion free of the therapeutic coating.
 2. Thesurgical stapling apparatus according to claim 1, wherein the innerconcentric portion of the surgical buttress includes a first concentricregion extending radially inwardly of an inner staple line of thesurgical buttress, and a second concentric region extending radiallyoutwardly of the inner staple line to a middle staple line of thesurgical buttress.
 3. The surgical stapling apparatus according to claim2, wherein the therapeutic coating is disposed only within the firstconcentric region of the surgical buttress.
 4. The surgical staplingapparatus according to claim 3, wherein the first concentric region isdefined between the inner staple line and a knife cut line of thesurgical buttress.
 5. The surgical stapling apparatus according to claim3, wherein the first concentric region is defined between the innerstaple line and an inner edge of the surgical buttress.
 6. The surgicalstapling apparatus according to claim 5, wherein the inner edge of thesurgical buttress is disposed radially inwardly of the circular knife ofthe staple cartridge assembly.
 7. The surgical stapling apparatusaccording to claim 2, wherein the therapeutic coating is disposedpartially within the second concentric region of the surgical buttress.8. The surgical stapling apparatus according to claim 1, wherein thetherapeutic coating includes a chemotherapy drug or an immunotherapydrug.
 9. The surgical stapling apparatus according to claim 1, whereinthe surgical buttress is disposed on the tissue facing surface of theanvil assembly or the staple cartridge assembly.
 10. The surgicalstapling apparatus according to claim 1, wherein the surgical buttressis disposed on the anvil shaft of the anvil assembly in spaced relationrelative to the tissue facing surfaces of the anvil and staple cartridgeassemblies.
 11. The surgical stapling apparatus according to claim 1,wherein the therapeutic coating is disposed on first and second sides ofthe surgical buttress.
 12. A staple cartridge assembly comprising: astaple cartridge including a tissue facing surface having stapleretaining slots defined therein, each staple retaining slot housing astaple therein, and a circular knife disposed radially inwardly of thetissue facing surface; and a surgical buttress releasably disposed onthe tissue facing surface of the staple cartridge, the surgical buttresshaving a circular configuration defining a central aperturetherethrough, the surgical buttress including an inner concentricportion having a therapeutic coating disposed thereon and an outerconcentric portion free of the therapeutic coating.
 13. The staplecartridge assembly according to claim 12, wherein the inner concentricportion of the surgical buttress includes a first concentric regionextending radially inwardly of an inner staple line of the surgicalbuttress, and a second concentric region extending radially outwardly ofthe inner staple line to a middle staple line of the surgical buttress.14. The staple cartridge assembly according to claim 13, wherein thetherapeutic coating is disposed only within the first concentric regionof the surgical buttress.
 15. The staple cartridge assembly according toclaim 14, wherein the first concentric region is defined between theinner staple line and a knife cut line of the surgical buttress.
 16. Thestaple cartridge assembly according to claim 14, wherein the firstconcentric region is defined between the inner staple line and an inneredge of the surgical buttress.
 17. The staple cartridge assemblyaccording to claim 16, wherein the inner edge of the surgical buttressis disposed radially inwardly of the circular knife of the staplecartridge.
 18. The surgical stapling apparatus according to claim 13,wherein the therapeutic coating is disposed partially within the secondconcentric region of the surgical buttress.
 19. The staple cartridgeassembly according to claim 12, wherein the therapeutic coating includesa chemotherapy drug or an immunotherapy drug.
 20. The staple cartridgeassembly according to claim 12, wherein the therapeutic coating isdisposed on first and second sides of the surgical buttress.